鄂西南香蒲科、黑三棱科、眼子菜科和茨藻科植物区系特征

FLORISTIC CHARACTERISTICS OF TYPHACEAE, SPARGANIACEAE,POTAMOGETONACEAE AND NAJADACEAE IN SOUTHWESTERN HUBEI

本文在采集标本基础上,结合分析大量有关资料,讨论了鄂西南香蒲科等四科植物区系特征。结果表明:1.区系组成包括5属20种2变种1杂种。其中有1新种1新变种和3个湖北分布新记录。2.区系种类丰富,起源古老,对湖北同类区系具有代表性。3.有一定比例的特有成分(8.70%)。4.区系地理成分复杂多样,但主要具有东亚亚热带一温带分布(26.09%)和世界性分布(26.09%)的性质。5.本区四科植物区系主要与处于我国地貌第三级阶梯上的省区发生密切联系。其区系分区,在亚区的划分上与陆生种子植物相同。

This paper deals with the floristic characteristics of Typhaceae etc. four families in southwestern Hubei, based on the specimens collected during the exploration to this area in 1985 and a lot of data surveyed. The results show:1. The flora so far known comprises 5 genera, 20 spp., 2 vars. and 1 hybrid, among which Sparganium fallax Graebn., Potamogeton perfoliatus L. and P. obtusifolius Mert. & Koch. are new records to Hubei, P. intortusifolius J. B. He et al. and Najas graminea Del. var. recurvata J. B. He et al. are new species and variety, respectively. 2. This area abounds in the species of these four families, as compared with the other provinces or districts of China, only next to Heilongjiang, Jilin, Yunnan, Xinjiang, Shaanxi, Intramongolia and the rest part of Hubei. Of 24 taxa of these four families found in the rest part of Hubei, 19 have been collected in this area. Thus the flora studied undoubtedly represents that of Hubei.3. The flora is of old origion, for the family Sparganiaceae being a Mesozoic one and the rest three at least Tertiary ones.4. The floristic element endemic to southwestern Hubei contributes a certain propotion (c. 8.70%) to the floristic composition.5. The floristic components are complex, 12 types of distribution area being divided. But its composition is mainly of cosmopolitan (26.09%) and temperate E. Asian (including Sino-Japanes) elements (26.09%).6. The flora is chiefly very close to that in the provinces or districts on the Tertiary terrace of the geomorphological map of China, namely east of China, which implies that there is an unanimity in the floristic regionalization at the level of the subregions between these four families and terrestrial seed plants.